Additive manufacturing systems and methods for the same

Additive manufacturing systems and methods for fabricating an article are provided. The additive manufacturing system may include a substrate and a layering device configured to fabricate a first layer of the article on the substrate. The layering device may include an optical beam source configured to generate an optical beam and a variable beam characteristics (VBC) fiber operably coupled with the optical beam source and configured to modify one or more beam characteristics, such as a wavelength, of the optical beam.